Interactive Lander Test (PC4)

The Rosetta mission's first interactive experiment test phase after the 2004 commissioning was conducted at the end of 2006 with the participation of the Rosetta Lander. The latter was switched on from 28th of November to 9th of December 2006 to do various instrument and system checks. The procedure comprised of the upload of new software for the experiments CIVA, MUPUS and ROLIS including follow-up safety-checks. On the experiment PTOLEMY, the mass spectrometer was activated for the first time, meanwhile the instruments related to SESAME were able to benefit from the maintenance of the orbiter's attitude control system by further determining facility characteristics for the CASSE experiment.

On the COSAC instrument, a measurement from commissioning was repeated. After the configuration of similar environmental conditions, a furnace check with nominal heat-up could be performed. Furthermore, two system tests were conducted on the Lander. At low environmental temperatures, the active descent system (ADS) was detecting too low gas pressure during one of the earlier passive checkouts. The new measurements indicated that this was a temperature-induced effect. After heating the ADS-sensor, the expected gas pressure was measured.

In the process of the Mars Swing-by preparation, the first battery test was done with the lander in autonomous flight configuration. To this end, the power supply and data lines between orbiter and lander were deactivated for approx. 50 minutes, and continuous telemetry was accumulated on the lander's central data storage. The experiment ROMAP was used in its ,Fast Mode' as the main source of data. After an unproblematic reactivation of data- and power-lines, lander and ROMAP-data was transferred from the data storage and demonstrated the expected behaviour. With this, the lander has successfully passed its first flight test with autonomous power-supply from batteries. Near the end of the test activities, the secondary battery was charged to about 80%, in preparation for the next lander tests at Mars Swing-by in early 2007.

Rosetta Lander Control Center

The next flight activity of the lander will be another test for the upcoming Mars Swing-by maneuver: the Rosetta orbiter will take on an orientation to the sun critical to the lander. It shall be verified, that no orbiter or lander components will be exposed to temperatures above limits. The thermal test is scheduled for 7th of January 2007.